1. Field of the Invention
The present invention relates to a gatekeeper and a load distributing method.
2. Description of the Related Art
In the so-called H323 network, i.e., a packet network in which service quality is not guaranteed and which is defined in H323 recommendation of the ITU, address conversion and access control are provided to an end point on the network by a gatekeeper (GK). The end point is a terminal like s personal computer. The end point on such an H323 network issues a gatekeeper discovery message to gatekeepers (GKs) on the network to look for one gatekeeper (GK) in which data of the end point is registered. When the plurality of gatekeepers (GKs) exist on the H323 network, each of the plurality of gatekeepers (GKs) receives the gatekeeper discovery message and sends back to the end point, a message indicating that the gatekeeper is possible to register the data. When receiving from the plurality of gatekeepers (GKs), the messages indicating that the registration is possible, the end point selects one of the plurality of gatekeepers (GKs) and carries out a subsequent process to the selected gatekeeper (GK).
In this way, in the conventional H323 network, when receiving the gatekeeper discovery message from the end point, the gatekeeper (GK) sends back the registration possible message to the end point, if the gatekeeper (GK) is possible to register the data of the end point regardless of the condition of other gatekeepers (GKs). Therefore, there is a possibility that the load of a specific one of the plurality of gatekeepers (GKs) on the H323 network becomes heavy. In this case, the loads of some gatekeepers (GK) become high extraordinarily, compared with the others, and the load of some gatekeepers (GK) become low extraordinarily, compared with the others. In such a case, though there is the plurality of gatekeepers (GKs) on the H323 network, the processing ability of each gatekeeper (GK) is not sufficiently utilized.
In conjunction with the above description, a distributed data processing system is disclosed in Japanese Laid Open Patent application (JP-A-Heisei 7-152702). In this reference, the distributed data processing system is composed of a plurality of terminal apparatuses and a plurality of data processing apparatuses possible to respond to processing requests from the terminal apparatuses, which are connected with the terminal apparatuses through a network. The data processing apparatus has a load situation monitoring section and a load data transmitting section. The load situation monitoring section generates load data showing its own load situation. The load data transmitting section transmits back the load data obtained by the load situation monitoring section in accordance with the request from the terminal apparatus. One data processing apparatus as a data management data processing apparatus has a load data management section and a load data inquiry processing section in addition to the load situation monitoring section and the load data transmitting section. The load data management section manages the load data in the plurality of data processing apparatuses. The load data inquiry processing section notifies the load data in accordance with an inquiry about the load data, which are managed by the load data management section. Each of the plurality of terminal apparatus has a first load data inquiry section which inquires the load data managed by the load data management section of the management data processing apparatus in case of a specific operation, a load data memory section which stores the load data notified from the first load data inquiry section in accordance with the load data inquiry from the first load inquiry processing section, and a load distribution control unit which distributes the loads of the processing requests to the data processing apparatuses based on the load data of the data processing apparatuses stored in the load data memory section.
Also, an automatic call delivering system and a communication network is disclosed in Japanese Laid Open Patent Application (JP-P2000-32146A). In this reference, a call from a customer is routed to one or more service agents. A gateway is provided to receive a telephone call in the public telephone line network, and a gatekeeper is connected to the gateway through a computer network. The gatekeeper delivers the call from the gateway to one of a plurality of agent terminals connected to the computer network to connect one service agent with the customer. An automatic call delivering server is connected to the computer network, and determines when the agent is usable, and instruct the gatekeeper to route the agent terminal, which is usable from the gateway.
Also, a traffic distributing apparatus is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 7-235939). In this reference, the traffic distributing apparatus is composed of a plurality of networks (3), a terminating unit (2) connected to each network (3) and transmitting and receiving a communication frame and a routing frame, and a plurality of relaying units (1) interconnecting the plurality of networks to relay the frame. Each relaying unit (1) is composed of a receiving section (11), a detecting section (15), a routing frame processing section (12), and a transmitting section (14). The receiving section (11) receives the communication frame and the routing frame transmitted from the terminating unit of a transmission source. The detecting section (15) detects a traffic amount of frames transmitted to the network of a transmission destination. The routing frame processing section (12) produces the routing frame to notify to the terminating unit of each network At this time, routing frame includes information of network entity title indicative of a medium call control address indicating an access point where the relaying unit is connected to the network and an address allocated to the relaying unit. Also, the routing frame processing section (12) produces the routing frame indicative of another relaying unit when the traffic amount exceeds a predetermined value. The transmitting section (14) transmits the communication frame to the transmission destination terminating unit and transmits the routing frame indicating the other relaying unit from the routing frame processing section to the transmission source terminating unit (2).